Rubber dam

ABSTRACT

The invention relates to a rubber dam for the isolation of one or more teeth in a patient&#39;s mouth, which comprises an annular perioral frame ( 2 ) to be arranged extraorally, an elastic and film-like covering means ( 1 ) which can be connected to the frame ( 2 ) and which in the untensioned state has a bag-shaped section ( 3 ) for insertion into the oral cavity, and a fastening means ( 6 ) for the intraoral fastening of the covering means ( 1 ). The fastening means ( 6 ) is formed by an elastic annular element ( 6 ) which can be inserted into the vestibule ( 8 ) in an elastically deformed state and then exerts a force on the covering means ( 1 ) which pushes the covering means ( 1 ) into the vestibule ( 8 ) and firmly retains it therein. When the rubber dam is inserted, the covering means ( 1 ) extends in a slightly tensioned state between the frame ( 2 ) and the fastening means ( 6 ) located in the vestibule ( 8 ) around the corners of the mouth and the lips ( 7 ) and intraorally in the upper jaw and in the lower jaw in a slightly tensioned state out of the vestibule ( 8 ), over the front sides of the teeth and in the palate and tongue area in the plane of the chewing surfaces, and pushes the lips, the corners of the mouth and the cheeks away from the teeth as well as the jaws apart and assists the opening of the mouth in this manner.

[0001] The present invention relates to a rubber dam for the isolationof a tooth or several teeth in a patient's mouth according to thepreamble of claim 1.

[0002] In dental practice it is necessary to carry out clean and drytreatments of teeth, as well as to isolate the teeth concerned. For thispurpose, the so-called rubber dam has been known for approximately 150years. In its original and simplest form, it consists of an elastic,flat covering means, mostly in the form of a rubber cloth, which isfastened in a frame outside the mouth. In order to isolate one or moreteeth, the covering means is pushed elastically into the oral cavity andtowards the teeth concerned. By means of a selective perforation, thecovering means can then be pulled over a tooth, wherein the edge of thehole formed in the elastic covering means rests against the tooth and inthis way ensures a circular seal around the tooth against fluids, suchas for example saliva or blood. By fastening the covering means to thetooth, it is reciprocally anchored against the frame which is arrangedoutside the mouth and into which the covering means is clamped. Theelasticity of the covering means causes the frame to be pushed firmlyagainst the face and the covering means to be fixed extraorally in astable manner. The high wall tensions which occur prevent the coveringmeans from being unintentionally sucked in by a dental suction deviceduring sucking off.

[0003] In addition to the named tasks, this known rubber dam alsorepresents a hygienic barrier and thus a protection against infectiousdiseases both for the patient and for the dentist and his assistants.Furthermore, it offers toxic protection against drilled-out amalgam orchemicals used by the dentist, such as disinfectants, and prevents theswallowing or aspirating of items, such as for example broken-off drillbits or tips of dangerous small instruments. As a result of theisolation of the operation field known from surgery, the rubber dammakes it easier for the dentist to concentrate. Further importantadvantages are a reduced treatment time, the elimination of frequentrinsing of the patient, the exclusion of moist breath with the resultthat the reconstructive materials used can be processed in a physicallyoptimum manner, and the prevention of bad breath which irritates theperson performing the treatment.

[0004] When the described rubber dam is used, the covering means takesthe shape of a funnel and is strongly stretched, in particular when thelateral teeth and above all the rear molars are treated. Due to the hightension, the covering means must be fastened in the mouth to one or moreteeth with the help of a strong clamp, with the risk that the teethconcerned are irreversibly damaged by the clamps. Even with the mostvaried methods of anchoring to the frame, the wall tension of thecovering means can be only poorly controlled. If the covering means isanchored only loosely to the frame, troublesome heavy creases occur, thecovering means is easily drawn into a suction device and the whole fitbecomes unstable a s a result of the low tension. If it is thus desiredfor example to avoid a troublesome creasing, the two-dimensionalcovering means must be substantially stretched with the named results.The dentist who—due to the size of the oral cavity—must carry outcomplicated treatments in any case in narrow spatial conditions, needsthe largest space that is anatomically possible without limitations. Asa result of the funnel shape of the covering means, the available spaceis so drastically reduced that treatment with dental instruments, suchas for example turbines, mirrors or suction devices, is possible only toa limited extent or often even impossible when using a rubber dam. Theselimitations are for example illustrated in an immediately apparentmanner in the book “Kofferdam in Theorie und Praxis” [Rubber dam intheory and practice], Reinhard Winkler, Quintessenz-Verlags GmbH, 1991,pages 47 and 56 (“angelegter Kofferdam” [fitted rubber dam]). Inaddition, with this isolation technique the whole oral vestibule isobstructed, covered and sealed. Furthermore, the covering means leadingout of the oral cavity in a straight line offers no means of retainingaccumulations of fluid, so that fluid, if it is not immediately suckedoff, runs out of the rubber dam and the mouth in an uncontrolled manner.Moreover, the fitted rubber dam causes the lips to be heavily presseddown or pressed flat and not a selective vertical upward pressing whichensures that the upper or lower lip is kept away or retracted, which isimportant for the dentist, and clears the way for the treatment of theteeth lying behind. Finally, patient acceptance is also not very highbecause of the external appearance of the fitted rubber dam (cf. also“Kofferdam in Theorie und Praxis”, see above, FIG. 477: “FertigeIsolation” [Completed isolation]).

[0005] The named problems of rubber dam systems, which are based on thedescribed method of operation of a funnel-shaped, reciprocally stressedcovering means between the clamped tooth and the extraoral frame, havenot been solved despite a variety of different and numerousmodifications to the frame, such as for example the choice of a round orsquare shape, to the covering means, such as for example the choice ofdifferent materials and strengths, and to the clamps. For these reasons,the rubber dam has not gained acceptance to date in dental treatmentpractice despite the above-mentioned and many other advantages.World-wide it is not used by most dentists or only used in certaintreatments, such as for example in endodontology for forensic reasons orin restorative treatments on the easily accessible front teeth. Even inindustrialized countries the rate of use is under 10%.

[0006] Another rubber dam is known from U.S. Pat. No. 5,340,313. Thisrubber dam has a bulge in the oral cavity, which renders the hightension of the covering means superfluous. A dimensionally stablehousing is used in order to keep the treatment space clear. Preciselythese are very restricting and are not at all suitable for the widevariety of treatments with dental instruments. In addition, a widevariety of shapes and sizes is required in order to treat all patients.As soon as dimensionally stable items are inserted into the oral cavity,disadvantages prevail, such as for example the restriction of freedom ofmovement and of the treatment space combined with the lack of a clearview, an expensive production or a failure to take into account theindividual anatomy. The above-described problems are solved onlyinsufficiently by this rubber dam.

[0007] In U.S. Pat. No. 4,889,490 a face mask for dental treatment isdisclosed which has a customary mask frame around which supports arearranged which are fastened to same, on which supports is fixed a filmwith an opening for the mouth. The mask frame can be pressed togetherand inserted between the lips, so that after being released it pushesthe lips apart laterally. The film serves to protect the patient's facefrom particles or fluids flying around. This device does not serve toisolate and dry out one or more teeth and pushes the lips apart merelylaterally, the hard profile also interfering with the treatment, as thetissue dynamic which is important in this area is lost.

[0008] U.S. Pat. No. 2,680,908 describes a rubber dam which comprisescomplicated shaping retaining elements. These are expensive to produceand, as dimensionally stable elements, have the above-nameddisadvantages.

[0009] DE 299 06 369 U1 describes a dental shielding device with ashielding film which has an oral-cavity eversion that is adapted to theshape of the oral cavity. The film is designed such that it can beinserted unstretched into the oral cavity and remains essentiallyunstretched—apart from the expansion in the area of the tooth to betreated—even after the perforated film is pulled over a tooth. Thereforethe film does not withstand a sucking off, but collapses and is suckedin as soon as a suction device comes near the wall. In order to preventthis, a strengthening of the eversion by material reinforcements or ribsis proposed, which however is associated with a complicated andexpensive production and the above-described disadvantages ofdimensionally stable parts. Attachment to the face is carried out forexample with the help of elastic bands which are placed around the ears,or a retaining device passing around the head. In addition to thecomplicated design, the awkward handling and discomfort for the patient,the lips are only pressed down, but not kept away or retracted in atargeted manner. Furthermore, the film lying untensioned in the oralcavity is resting against the palate and the tongue. This not only hasthe disadvantage that patients find this wallpaper-like lining of thepalate and the limited mobility of the tongue unpleasant(claustrophobia), but also that a gag reflex is triggered in patientswho react extremely sensitively.

[0010] Further rubber dam designs, each being fixed to the teeth in theoral cavity essentially in the shape of an untensioned bag, also havethe same disadvantages and are disclosed in DE 197 04 904 and WO98/34559.

[0011] The object of the present invention is to design a rubber dam forthe isolation of a tooth in a patient's mouth such that it can haveunlimited use in dental practice and the named disadvantages areeliminated.

[0012] The features of claim 1 serve to achieve this object.Advantageous embodiments of the rubber dam are the subject of therespective dependent claims.

[0013] The basic idea of the present invention is that the rubber damcomprises an annular frame for resting against the perioral facial area,an elastic film-like covering means which can be connected to the frameand in an untensioned state has a bag-shaped section for insertion intothe oral cavity, and a fastening means for the intraoral fastening ofthe covering means, the fastening means being formed by an elastic andannular element which is adapted in order to be inserted in anelastically deformed state into the vestibule and to exert a force onthe covering means which pushes the covering means into the vestibuleand retains it therein, so that, when the rubber dam is inserted, thecovering means extends in a slightly tensioned state between theextraoral frame and the fastening means located in the vestibule aroundthe lips and the corners of the mouth and intraorally, in the upper jawand in the lower jaw, in a slightly tensioned state out of thevestibule, over the external surfaces and the chewing surfaces of theteeth and in the palate and tongue area in the plane of the chewingsurfaces, and the lips, cheeks and corners of the mouth are pushed awayfrom the teeth and a force directed upward is exerted on the upper jawand a force directed downward is exerted on the lower jaw. The shape ofthe bag-shaped section can vary to a large extent and have any desiredthree-dimensional shape with an opening. The only deviation from thedescribed course of the covering means is in the area of the teeth to betreated, in which the covering means is perforated and pulled over oneor more teeth.

[0014] The rubber dam according to the invention therefore consists of apassive, simple shape comprising an elastic covering means and aperioral frame which are brought into a dynamic shape with the help ofan elastic and annular fastening means to be clamped into the vestibule,wherein the three-dimensional shape of the oral cavity is accommodatedby a slight stretching of the covering means and thus size differencesand an individual anatomy are taken into account.

[0015] The annular fastening means inserted into the vestibule, togetherwith the covering means, advantageously causes the cheeks and thecorners of the mouth to be pushed apart transversally and the upper andlower jaw as well as the lips to be pushed apart vertically. To thisend, the covering means is fixed extraorally by the perioral frame,while intraorally the annular fastening means in the vestibule effects afurther fixing of the covering means, so that the slightly tensionedcovering means lying in between extends around the lips and the cornersof the mouth and in abutment to these, as a result of which forces areexerted by the slightly stretched covering means on all the perioralstructures that push these radially apart. The annular fastening meansfollows the course of the vestibule preferably up to the rearmostmolars. In the lower jaw and the upper jaw, the covering means extendsin a slightly tensioned state between the fixing in the vestibule overthe front sides of the teeth and the chewing surfaces of the teeth inthe plane of the chewing surfaces. The only deviation from this courseis in the area of the teeth to be treated, in which area the coveringmeans is perforated and pulled over the teeth. In this way, thefastening means, pushing itself into the vestibule due to itselasticity, effects that it pushes the jaws apart either itself bypressing directly onto the oral mucous membrane or via the slightlystretched covering means, which exerts corresponding forces on: thechewing surfaces of the teeth and on the lips, or by a co-operation ofthese forces. As a result of the described arrangement, for one thing aforce directed spherically outwards is therefore transferred to the lipsand the corners of the mouth by the covering means, the force vectorsbeing ideally arranged to effect a circular retraction of the lips andthe corners of the mouth. This is advantageous both for the dentist andfor the patient. Thus it offers the dentist optimum conditions for alltypes of dental treatment. Due to the lips and the corners of the mouthbeing gently pushed apart or retracted, the teeth to be treated becomevisible. Nevertheless, the mobility of the perioral tissue is maintainedand the lips and the corners of the mouth remain deformable according tothe treatment requirement. Dimensionally stable shields and retractingelements are thus not necessary for this task. As the covering means isthin and elastic, a lip or a corner of the mouth can—if necessary—beretracted or kept away even further with instruments. Furthermore, thedescribed forces pushing the jaws apart give the patient a pleasantfeeling because they help him to open his mouth and also to keep it openover a long period without difficulty.

[0016] When the rubber dam is inserted, the forces exerted by theannular fastening means through its spring effect are thereforetransferred vertically, transversally and sagitally indirectly oressentially indirectly to the oral cavity, in that after insertion intothe vestibule the rubber dam produces a tension in the whole coveringmeans, i.e. the wall of the rubber dam. In this tensioned state, thecovering means, which is open at the front and closed towards thethroat, surrounds the lips and the corners of the mouth in a circularmanner starting from the extraoral frame, and extends into thevestibule, out of this again and—with the exception of the areas inwhich the covering means is perforated and pulled over the teeth—overthe external and chewing surfaces of the teeth, and covers the tongueand the palate in the chewing plane. As a result of this course taken bythe covering means, the lips, the corners of the mouth, the cheeks andthe mouth are kept apart and sagital forces stabilize the rubber dam dueto the reciprocal tensioning between the extraoral fixing provided bythe perioral frame and the intraoral fixing provided by the fasteningmeans.

[0017] When using the rubber dam according to the invention, the maximumsize of the oral cavity is isolated so that the largest possibleisolation area is formed without interfering elements. The retractedcheeks, lips and corners of the mouth substantially enlarge thevestibule which is covered in a circular manner by the elastic coveringmeans up to deep into the vestibule and offers direct access to theteeth.

[0018] As the covering means in the lower jaw covers the floor of themouth and the tongue in the plane of the chewing surfaces of the teeth,a free space remains for the tongue, which is very important forpatients as the swallowing process can be carried out unhindered and thetongue is gently kept away by the covering. In the upper jaw, thecovering of the hard and soft palate in the plane of the chewingsurfaces brings about that unpleasant sensations caused by a contactbetween the palate and the covering means are avoided and patients witha gag reflex are given particular consideration by ensuring a gentletreatment.

[0019] As a result of the only low tension of the covering means, it canbe impressed if necessary both in the upper and lower jaw, for examplein order to create space for suction devices or other instruments.Through the elastic tensioning force of the annular fastening meanswhich pushes the stretchable covering means into the vestibule in auniform and circular manner, creasing is largely avoided.

[0020] The covering means is also held such that after perforation itnaturally slips around the tooth and is pulled downward by the elasticannular fastening means. In contrast to this, with the previously knownrubber dam, in which a flat covering means in the form of a rubber clothis pulled up to the lateral molars, pull forces occur which attempt topull the covering means off the tooth, so that broad and strongretaining clamps are necessary. It is clear that an elastic, spatialcovering means virtually adapted to the oral cavity must be stretched toa significantly lesser extent than such a flat covering means, so thatcorrespondingly gentler stretching forces are produced. Due to the onlyslight stretching of the covering means, it is also possible to isolatethe gums together with the teeth to be treated.

[0021] The application of a rubber dam according to the invention can becarried out by one person by hand without instruments in a simple andtime-saving manner, by firstly inserting the bag-shaped section of thecovering means into the patient's mouth. The patient takes a shortbreath in through the mouth so that the covering means is pulled into acrease-free shape by the negative pressure produced. Then the annularfastening means is vertically elastically pressed together with one handand both ends left and right are held with the other hand and are pulledbackwards. The fastening means now corresponds to the spatial course ofthe vestibule and, with a slight swivelling, can successively beinserted laterally and carefully guided under the lower or upper lip.After release, it springs open in accordance with the shape of theindividual anatomy and fixes the covering means intraorally in theabove-described manner. A very good shape is produced which offers idealconditions for treatment. The rubber dam feels pleasant to patientsbecause the spring force makes it easier to keep the mouth open for alonger period and half the face is not covered. After insertion of theintraoral fastening means, the rubber dam stabilizes automatically andadvantageously also remains stable if the patient makes dynamic oralmovements, such as opening and closing, lateral movements or forward andbackward movements.

[0022] In a preferred embodiment, when the rubber dam is inserted, thereexists between the fastening means and the covering means an equilibriumof forces in which the fastening means is supported at least in the areaof the lips by the slightly stretched covering means and is retracted orkept away from the tissue bordering the vestibule in such a way that thefastening means itself exerts no or only a slight pressure on thistissue. This means that the fastening means, as a result of its springeffect, pushes the covering means into the vestibule in the respectiveareas, but not so far that it is clamped under pressure between the oralmucous membrane and the fastening means. Rather, there the coveringmeans is placed by the fastening means only lightly against the oralmucous membrane or is held “suspended” in front of this in the area ofthe fixing. This ensures that the transfer of force from the rubber damto the lips, the corners of the mouth, the cheeks and the jaws iseffected exclusively or at least almost exclusively via the coveringmeans resting against the tissue and the spring effect of the fasteningmeans is transferred indirectly via the covering means. This has theadvantage that no significant direct transfer of force takes placethrough the annular and mostly thin fastening means to the particularlysensitive oral mucous membrane, which can make the rubber dam feelunpleasant to wear and finally lead to pressure marks. This is importantin particular in the area of the lips, i.e. the front teeth, as thedanger is particularly high there that a pressure is exerted in anunpleasant manner on parts of the oral mucous membrane with an osseousbase or other sensitive parts. In the area of the cheeks, however, thefastening means can position or push the covering means directly againstthe lateral mucous membrane, an equilibrium of forces then developingbetween the covering means, the fastening means and the soft tissue. Thefastening means is then preferably supported by the covering means insuch a way that the fastening means pushes the covering means merelyagainst the insides of the cheeks and not against the oral mucousmembrane in the deepest possible course of the vestibule, but holds thecovering means at a distance from the oral mucous membrane. In mostcases, no great forces are required in order to push the soft tissue inthe area of the cheeks laterally outwards, and the tissue is relativelyinsensitive with respect to such forces. In any case, it is possible toensure that the pressure exerted by the fastening means on the oralmucous membrane is not traumatic. Instead, the transfer of force occursover a wide area, and therefore distributed, via the covering meansresting against the tissue. To this end, the covering means and thefastening means must be suitably matched with respect to each other. Alarge number of different factors, such as the dimensions of the twocomponents and their mechanical properties, play a part in thismatching. However, the corresponding adaptation of the fastening meansand the covering means can be carried out in any case rapidly and easilyby a person skilled in the art.

[0023] In a further preferred embodiment, the opening of the bag-shapedsection of the covering means is round or oval. It is also advantageousif the end located opposite the opening of the bag-shaped section of thecovering means is round or oval. Perpendicular to the opening, thebag-shaped section of the covering means is preferably straight-walledwith parallel side walls or side walls extending conically with respectto each other. While almost any desired shapes are conceivable andpossible, an efficient and inexpensive producibility is all the moreguaranteed, the simpler the shape.

[0024] Furthermore, it is advantageous if the opening of the bag-shapedsection of the covering means is larger than the mouth opening. As thebag-shaped section of the covering means also has a larger diameter,circular, in the tensioned state in the oral cavity than the mouthopening, the lips and the corners of the mouth are held apart in theabove-described manner. The covering means can compensate for the longerpath caused by the lips and the corners of the mouth only by stretching.

[0025] It is preferred that the covering means is pre-stamped,pre-marked or can be perforated as desired. The position of the teethwhen the covering means is inserted is shown by the pre-punching orpre-marking. In this way or if the covering means can be perforated asdesired, it is easily possible for a user to pull the covering meansover one or more teeth.

[0026] Furthermore, it is advantageous if the covering means consists oflatex. Such covering means have a high modulus of elasticity whichprovides the necessary stretchability.

[0027] In a preferred embodiment, the covering means has one or moreperforations. Thus a perforation can be provided which enables breathingthrough the mouth if a patient has difficulty breathing through thenose. This perforation to enable breathing through the mouth isadvantageously arranged in the palate area of the upper jaw. It does notinterfere with the treatment because saliva and moist mucous membraneare kept away by the covering means. Furthermore, a perforation can beprovided through which a saliva ejector can be inserted and fixed.However, such a perforation is normally not necessary because apatient's own saliva, which is separated by the covering means fromwater, blood, chemicals or other fluids or contaminations, can beswallowed as usual. If a perforation is provided for a saliva ejector,it is further advantageous to form a further perforation in the coveringmeans in the palate area, in order that air can be subsequently suckedup through this, thus preventing a vacuum behind the covering meanswhich would cause the covering means to press against the inside of theoral cavity.

[0028] Ring-shaped elements of different diameters can be provided asfastening means for different mouth sizes. As a result of thestretchability of the covering means, it is in a position to compensatefor the size differences of the oral cavity of patients, such as forexample of adults with tray sizes S, M and L, and to easily adapt toindividual anatomical differences or special features, such as forexample a strong musculature, macroglossia (enlarged tongue), a mouthopening that is too small or too large or a limited mouth opening.However, it is advantageous if annular fastening means which fit therespective patient are chosen. They can be colour-marked as to thespring force within the same diameter, so that all sizes and tensioningforces can be covered in a continuously variable manner. As a result ofthe combination of the suitably shaped covering means and differentannular fastening means, a finely graduated and controllable system iscreated which is suited to all conditions.

[0029] The annular fastening means can be made of plastic, glass fibresor metal. It can have a round, rectangular or hexagonal cross-section.Furthermore, it can be round, elliptical, asymmetric or spatiallyanatomically slightly deformed, the easily producible round shapehowever being sufficient in most cases.

[0030] It is possible that the annular fastening means is designed to besterilizable, disinfectable and reusable or as a disposable article.

[0031] In addition, it is also advantageous if the annular fasteningmeans is covered by an elastic tube. This provides a protection againstpressure marks. Also in order to prevent pressure marks, the annularfastening means can advantageously have small notches for the lipfrenulums arranged in the middle of the upper and lower jaw. Thesemeasures are not necessary in the case of the above-described preferredembodiment, in which the fastening means is kept away by the coveringmeans in such a way that it does not rest against the oral mucousmembrane or only rests lightly against it.

[0032] In a preferred embodiment, the frame is fixedly connected to thecovering means. To this end, the frame can preferably be incorporatedinto the covering means or glued to this. However, it is alsoadvantageous if the frame is not fixedly connected to the coveringmeans, but is subsequently fastened to this or is attachable, so thatthe state of tension of the covering means can be additionallycontrolled by the manner in which the frame is fastened or attached.Such a control possibility can advantageously also be realized byconstructing the frame as an adjustable ring.

[0033] The frame can advantageously be made of plastic. Furthermore, itis advantageous if the frame has a slight straightening or a recess forthe nose. Furthermore, it is advantageous if the frame is anatomicallyspherically curved to fit the shape of the face, so that the frame canlie flat against the perioral facial areas.

[0034] If one tooth or several teeth together with the gums are to beisolated, it is preferred if the rubber dam comprises an adhesivewindow. This has the shape of an anatomically arched frame which can beplaced over the teeth and onto the alveolar process. Towards the oralcavity, this frame has retaining means, for example in the form of clawsor bent-back edges, with which retaining means the covering means, whichfor example in comparison with the mere isolation of a tooth isperforated or punched to a somewhat larger extent, can be fastened tothe adhesive window.

[0035] It is possible that the frame of the adhesive window isplastically deformable. In this case, it is advantageous if the framecomprises a material which can be cured by light irradiation. On theother hand, it is also possible for the frame to be designed elasticsuch that the adhesive window can be placed slightly resiliently overthe teeth and onto the alveolar process. The adhesive window can befixedly connected to the covering means. Additionally, it isadvantageous if the adhesive window can be provided on its underside,i.e. towards the mucous membrane and the teeth, with a reversibleadhesive suitable for moist mucous membrane and/or on the side facingthe oral cavity with an adhesive which effects a tight connectionbetween the adhesive window and the teeth or the covering means,respectively. Furthermore, it is preferred that the adhesive window onits side facing the vestibule has means which the annular fasteningmeans can engage and thereby firmly retain the adhesive window on theteeth and the gums. With suitable technology such as for example aborder wire and a matrix part which fits the profile—similar to bracketsin orthodontics—forces can also be transferred laterally which press theside of the adhesive window facing the tongue and palate advantageouslygently and tightly against the mucous membrane. In most cases, however,the firm vestibular retaining of the adhesive window by the annularfastening means is sufficient against the pulling forces of the coveringmeans, because the system works only with slightly stretched coveringmeans.

[0036] Perforated or with an adhesive window, the rubber dam accordingto the invention, which can be produced very simply and thereforeeconomically, is suitable for all treatments to teeth or gums. Evenextractions or implants can be carried out unhindered and in a medicallycorrect manner in the covered state.

[0037] In the following, the invention is explained in more detail withreference to embodiments which are illustrated in the drawings.

[0038]FIG. 1 shows a perspective view of a covering means connected to aframe.

[0039]FIG. 2 shows a top view of an annular elastic fastening means.

[0040]FIG. 3 shows a partly sectioned view of the lower jaw after theapplication of a rubber dam according to the invention.

[0041]FIG. 4 shows a partly sectioned view of the lower jaw after theinsertion of the covering means into the oral cavity and before theinsertion of the fastening means into the vestibule.

[0042]FIG. 5 shows a median section through the oral cavity after theapplication of a rubber dam according to the invention.

[0043]FIG. 6 shows a cross-section of the oral cavity after theapplication of a rubber dam according to the invention, the rubber dambeing perforated on the left and right in the upper jaw and pulled overa tooth.

[0044]FIG. 7 shows a view of a patient's head after the application of arubber dam according to the invention.

[0045]FIG. 8 shows a perspective view of an adhesive window.

[0046]FIG. 8a shows a perspective view of the adhesive window from FIG.8 after the fastening of the covering means.

[0047]FIG. 9 shows a sectional view of the adhesive window along theline IX-IX from FIG. 8.

[0048]FIG. 10 shows a sectional view of the adhesive window along theline X-X from FIG. 8.

[0049] The covering means 1 represented in perspective view in FIG. 1 isformed by a thin, flexible and elastic film-like material and isconnected at its edge to a frame 2. The covering means 1 together withthe frame 2 is essentially hat-shaped and has a bag-shaped section 3.The external shape of this section 3 has the design of a truncated cone,with a round opening (not shown), a round base part 4 and a side wall 5tapering towards the latter. FIG. 2 shows an annular fastening means inthe shape of a circular, elastic ring 6.

[0050] In order to fasten the rubber dam in a patient's oral cavity, atfirst the bag-shaped section 3 of the covering means 1 is introducedinto the patient's mouth and the frame 2 is placed around the mouthagainst the perioral facial areas. The ring 6 is then pressed togetherelastically such that it can be inserted into the vestibule along itsentire course up to the rearmost molars. After release, the ring forcesitself into the vestibule due to its elasticity, as a result of which itpushes the covering means 1 into the vestibule in the upper and lowerjaw along the entire vestibule and firmly retains and fixes the coveringmeans therein. In the process, the covering means 1 is stretched andextends in a slightly tensioned state both between the extraoral frame 2and the vestibule and intraorally. It is apparent from FIG. 3, whichshows a view of the lower jaw after the insertion of the rubber dam intothe mouth, that the covering means 1 extends from the frame 2, restingagainst the face, along the facial skin around the corners of the mouthand the lips 7 and intraorally in the vestibule 8. The ring 6 clampedinto the vestibule 8 pushes, together with the covering means 1, theupper and lower jaw vertically and the cheeks and the corner of themouth transversally apart.

[0051]FIG. 4 shows a view of the lower jaw after the insertion of thebag-shaped section 3 of the covering means 1 into a patient's oralcavity and before the insertion of the ring 6 into the vestibule 8. FIG.4 therefore shows in comparison with FIG. 3 the shape 9 of the coveringmeans 1 arranged in the oral cavity in an untensioned state before it isbrought into the slightly stretched shape (FIG. 3) with the help of thering 6 and expands the vestibule 8. The covering means 1 is constructedsuch that the opening of the bag-shaped section 3 is larger than themouth opening 11. At the same time, the dimensions of the bag-shapedsection 3 are chosen such that it is smaller in an untensioned statethan the area of the oral cavity to be isolated. In the present case,the depth of the section 3 in an untensioned state is less than thedistance between the lips and the rearmost point of the vestibule in thearea of the molars, and the diameter of the section 3 is smaller thanthe distance between the vestibule sections in the area of the sideteeth of the lower jaw and the upper jaw. In any case, it is importantthat the dimensions of the untensioned shape 9 are chosen such that,after the insertion of the ring 6 into the vestibule, the covering means1 is only slightly stretched regardless of the exact mouth size, i.e.with a small mouth a sufficient wall tension remains in order to preventa sucking in by a suction device and with a large mouth, even with thegreater stretching which is then necessary, no traumatic forces occur.Taking these factors into account, the covering means can be made instandard sizes, for example for children and for adults.

[0052] The comparison between FIGS. 3 and 4 illustrates the differencebetween the space taken up by the untensioned covering means 9 and thelarger isolation area achieved after the insertion of the ring 6. Thecovering means 1 must compensate for this difference by stretching, as aresult of which it is brought into a slightly tensioned shape. As thecovering means 1 as described is not constructed to have theanatomically correct form and with sufficient material reserves for thesmaller mouth opening, it is apparent that the covering means 1 extendsaround the corners of the mouth and the lips 7 in a tensioned state,because the covering means 1 can compensate for the longer path causedby the corners of the mouth and the lips 7 only by stretching. Asillustrated in FIG. 5, the covering means 1 guided in a tensioned statearound the corners of the mouth and the lips 7 causes the lips 7 and thecorners of the mouth to be held apart spherically. In addition to thebarrier function, the covering means 1 can therefore also fulfil theimportant task of circular retraction of the perioral tissue.

[0053] In addition to FIG. 5, FIG. 6 in particular shows that thecovering means 1 extends intraorally out of the vestibule 8, over thefront sides of the teeth 13 and their chewing surfaces. In the palateand tongue area, the covering means 1 extends in a slightly tensionedstate in the plane of the chewing surfaces of the teeth 13, so that thetongue and the palate are not touched. The covering means leaves thisplane only in the area of teeth 14, 15 to be isolated.

[0054] Furthermore, it is represented in FIGS. 5 and 6 that the ring 6pushes the covering means 1 only so far into the vestibule 8 that thecovering means 1 is not firmly clamped at the deepest point of thevestibule 8 between the ring 6 and the oral mucous membrane. Rather, thering 6 “is suspended” in the area of the lips in the vestibule 8 and issupported by the covering means 1 such that the ring exerts no directpressure on the tissue (see FIG. 5), and extends in the area of thecheeks spaced from the oral mucous membrane in the deepest possiblecourse (see FIG. 6). This is achieved by the fact that the spring effectof the ring 6 and the stretchability of the covering means 1 aresuitably adapted to each other. As is apparent from FIG. 6, only in thearea of the cheeks the ring 6 pushes the covering means 1 directlylaterally against the oral mucous membrane and therefore together withthe covering means 1 the cheeks apart. In this area, in which anequilibrium of forces is established between the ring 6, the coveringmeans 1 and the soft tissue, the pressure is however not as critical, assoft tissue is involved which can be easily pushed outwards and as aresult of the lack of an osseous base is relatively insensitive.Depending on the structure of the cheeks, the vertical course of thecovering means 1, represented in FIG. 6, between the fixings in theupper jaw and in the lower jaw effected by the ring 6 may also be notstraight, but curved inwards slightly towards the teeth as a result ofthe counterpressure of the soft tissue.

[0055] In FIG. 7, the patient's head is shown after the application ofthe rubber dam. As a result of the stretching of the covering means 1and the fixing elements 2 and 6, the rubber dam stabilizes itselfautomatically after the insertion of the intraoral fastening means 6. Ifit is established during application that the ring 6 is too large or toosmall, it can be quickly replaced by another one. It is essential thatthis thin ring 6 lies almost invisible in a zone which does not disturbthe person performing the treatment, and nevertheless makes the passiveshape 9 of the covering means 1 into a slightly tensioned covering ofthe isolation area and makes the oral cavity into a pleasant operatingarea.

[0056] In FIG. 8, an adhesive window 16 is represented which is used ifa tooth or several teeth together with the gums are to be isolated. Theadhesive window 16 has two lateral sections 17, 18 which extend parallelto each other and which are connected at their ends by two arcuatesections 19. The dimensions are chosen such that the adhesive window 16as an anatomically shaped frame can be placed with the arches 19 overthe teeth and the lateral sections 17, 18 onto the alveolar process insuch a way that one or more teeth as well as a part of the adjoining gumis freely accessible between the arches 19 of the window 16.

[0057] It is apparent from FIG. 9, which shows a section through theadhesive window 16 placed onto the teeth along the line IX-IX from FIG.8, that the adhesive window 16 is provided at its side facing the teethwith an adhesive 21, so that a safe and tight connection between theadhesive window 16 and the teeth and the gum is guaranteed.

[0058] At the edge, lying within the area delimited by the adhesivewindow 16, of the frame sections 17, 18, 19, claws 20 are provided whichare formed by bent-back areas of the frame sections 17, 18, 19 and onwhich the covering means 1 can be fastened. This is illustrated in FIG.10 which shows a section through the adhesive window 16 placed onto theteeth along the line X-X from FIG. 8. These claws 20 can be providedalong all the inside edges of the frame sections 17, 18, 19. In order tofasten the covering means 1 to the adhesive window 16, the coveringmeans 1 is perforated and placed over the adhesive window such that theedges of the perforation are grasped by the claws 20 and the perforationis kept in an expanded state (see FIG. 8a). However, it is also possiblethat the claws 20 are provided merely on the inside edges of thehorizontal frame sections 17, 18 and the sealing along the arch sections19 takes place by the fact that the covering means rests against thesein a tensioned state. In this case, the arch sections 19 can also beprovided on their surface with an adhesive which assists this sealing.

1. Rubber dam for the isolation of a tooth or several teeth in apatient's mouth comprising an annular frame (2) for resting against theperioral facial area, an elastic film-like covering means (1) which canbe connected to the frame (2) and in an untensioned state has abag-shaped section (3) for insertion into the oral cavity, and afastening means (6) for the intraoral fastening of the covering means(1), characterized in that the fastening means (6) is formed by anelastic and annular element (6) which is adapted in order to be insertedin an elastically deformed state into the vestibule (8) and to exert aforce on the covering means (1) which pushes the covering means (1) intothe vestibule (8) and firmly retains it therein, so that, when therubber dam is inserted, the covering means (1) extends in a slightlytensioned state between the extraoral frame (2) and the fastening means(6) located in the vestibule (8) around the lips (7) and the corners ofthe mouth and intraorally in the upper jaw and in the lower jaw in aslightly tensioned state out of the vestibule (8), over the externalsurfaces and chewing surfaces of the teeth and in the palate and tonguearea in the plane of the chewing surfaces, and the lips, cheeks andcorners of the mouth are pushed away from the teeth and a force directedupward is exerted on the upper jaw and a force directed downward isexerted on the lower jaw.
 2. Rubber dam according to claim 1,characterized in that, when the rubber dam is inserted, an equilibriumof forces develops between the covering means (1) and the fasteningmeans (6), in which equilibrium the fastening means (6) is supported bythe slightly tensioned covering means (1) such that, at least in thearea of the lips, the fastening means (6) does not press or only lightlypresses against the tissue bordering the vestibule and the transfer offorce from the rubber dam to the lips, the corners of the mouth, thecheeks and the jaws takes place via the covering means (1).
 3. Rubberdam according to claim 1 or 2, characterized in that the opening of thebag-shaped section (3) of the covering means (1) is round or oval. 4.Rubber dam according to one of the preceding claims, characterized inthat the end located opposite the opening of the bag-shaped section (3)of the covering means (1) is round or oval.
 5. Rubber dam according toone of the preceding claims, characterized in that the bag-shapedsection (3) of the covering means (1) is straight-walled or conical. 6.Rubber dam according to one of the preceding claims, characterized inthat the opening of the bag-shaped section (3) of the covering means (1)is larger than the mouth opening (11).
 7. Rubber dam according to one ofthe preceding claims, characterized in that the covering means (1) ispre-stamped, pre-marked or can be-perforated as desired.
 8. Rubber damaccording to one of the preceding claims, characterized in that thecovering means (1) consists of latex.
 9. Rubber dam according to one ofthe preceding claims, characterized in that the covering means (1) has aperforation in order to enable breathing through the mouth.
 10. Rubberdam according to claim 9, characterized in that the perforation forbreathing through the mouth is located in the palate area of the upperjaw.
 11. Rubber dam according to claim 9, characterized in that theperforation for breathing through the mouth is located in the area ofthe lower jaw.
 12. Rubber dam according to one of the preceding claims,characterized in that the covering means (1) has a perforation for asaliva ejector.
 13. Rubber dam according to claim 12, characterized inthat the covering means (1) has a perforation for subsequent suction ofair.
 14. Rubber dam according to one of the preceding claims,characterized in that annular elements of different diameter areprovided as fastening means (6) for different mouth sizes.
 15. Rubberdam according to one of the preceding claims, characterized in that theannular fastening means (6) has a round, rectangular or hexagonalcross-section.
 16. Rubber dam according to one of the preceding claims,characterized in that the annular fastening means (6) is round,elliptical, asymmetric or spatially anatomically slightly curved. 17.Rubber dam according to one of the preceding claims, characterized inthat the annular fastening means (6) is made of plastic, glass fibres ormetal.
 18. Rubber dam according to one of the preceding claims,characterized in that the annular fastening means (6) is sterilizable ordisinfectable and reusable.
 19. Rubber dam according to one of claims 1to 17, characterized in that the annular fastening means (6) is producedas a disposable article.
 20. Rubber dam according to one of thepreceding claims, characterized in that the annular fastening means (6)is covered by an elastic tube.
 21. Rubber dam according to one of thepreceding claims, characterized in that the annular fastening means (6)has small notches for the lip frenulums.
 22. Rubber dam according to oneof the preceding claims, characterized in that the frame (2) is fixedlyconnected to the covering means (1).
 23. Rubber dam according to claim22, characterized in that the frame (2) is incorporated into thecovering means (1) or adhesively connected to the covering means (1).24. Rubber dam according to one of the preceding claims, characterizedin that the frame (2) is made of plastic.
 25. Rubber dam according toone of the preceding claims, characterized in that the frame (2) has aslight straightening or a recess for the nose.
 26. Rubber dam accordingto one of the preceding claims, characterized in that the frame (2) isan adjustable ring.
 27. Rubber dam according to one of the precedingclaims, characterized in that the frame (2) is anatomically sphericallycurved to fit the shape of the face, so that the frame can flatly abut.28. Rubber dam according to one of the preceding claims, characterizedin that the rubber dam comprises an adhesive window (16) for the jointisolation of teeth and gums in the form of an anatomically curved frame(17, 18, 19) which can be placed over the teeth and onto the alveolarprocess and, on the side facing away from the teeth, has retaining means(20) with which the covering means (1) can be fastened to the adhesivewindow (16).
 29. Rubber dam according to claim 28, characterized in thatthe frame (17, 18, 19) is plastically deformable.
 30. Rubber damaccording to claim 29, characterized in that the frame (17, 18, 19)comprises a material which can be cured by light radiation.
 31. Rubberdam according to claim 28, characterized in that the frame (17, 18, 19)is designed to be elastic such that the adhesive window (16) can beplaced slightly resiliently over the teeth and onto the alveolarprocess.
 32. Rubber dam according to one of claims 27 to 31,characterized in that the adhesive window (16) can be provided towardsthe mucous membrane and the teeth with a reversible adhesive suitablefor moist mucous membrane.
 33. Rubber dam according to one of claims 27to 32, characterized in that the retaining means (20) are claws orbent-back edges.
 34. Rubber dam according to one of claims 27 to 33,characterized in that the adhesive window (16) is fixedly connected tothe covering means (1).
 35. Rubber dam according to one of claims 27 to34, characterized in that the adhesive window (16), facing the vestibule(8), comprises means (21) through which the annular fastening means (6)can firmly retain the adhesive window (16) on the teeth.
 36. Rubber damaccording to one of claims 27 to 35, characterized in that the adhesivewindow (16) can be provided on the side facing the oral cavity with anadhesive which effects a tight connection with the covering means (1).